Re: Transaction Locks

Sampath Shrinivasan (sampath@netcom.com) wrote: : We are running Informix SE 5.o on Unisys U6000/100 using SVR4.0.1.2. : Oflate we are having some problem with the updates in a transaction. Whenever : the number of row updates in a transaction go beyond a couple of hundred : records, we get an error "Unable to update row". Informix said that it could : be due to the number of locks available in the system. Can anybody advise me : as to how to increase the number of locks ? Should i increase the shared : memory parameters or the number of semaphores in the system ?. I tried to : increase the number of file locks(FCLKREC) but that didnot help. Also, is : there a formula which will help me to set this parameter based on the maximum : number of updates in any one transaction ? : Regards : sampath@netcom.com A couple of hints. You probably don't need to look at the kernel parameters like LCLKREC & SEMMXXXX.....If OnLine runs, it runs and you probably don't need to mess with the kernel. You need to pump up the LOCKS parameter in your $INFOMIXDIR/etc/tbconfig file. Make it really big...they're small (just a few bytes of shared memory apiece). What is the lock mode on the tables you are updating? It may make some sense to take the lock mode down from page (the default) to row (this'll use up more locks if you do it, but they will have less chance of conflict. You're probably hitting a situation where one row update locks a page and other updates want that page. -- =========================================================================== jlumbley@netcom.com (Joe Lumbley) Dallas, Texas Watch for my _INFORMIX DBA SURVIVAL GUIDE_ in Fall '94 from Prentice Hall! ===========================================================================